For he whom God hath sent speaketh the words of God: for God giveth not the Spirit by measure unto him.John 3:34
Think of the best preacher you have ever heard.
There is no doubt that the Lord blesses men to preach the gospel with power and in a mighty way at times.
Jesus even said there is no greater than John the Baptist!
Verily I say unto you, Among them that are born of women there hath not risen a greater than John the Baptist:Matthew 11:11a
But each of these men had only a measure or portion of the Spirit of God.
When Jesus spoke, He was filled with ALL of the Spirit of God not just a portion. His word is final and authoritative. His word should be used to define all other passages of the Bible and elements of doctrine.